What do we really know about nutrition?

We’ve all seen the headlines about some food or nutrient found to be terrific for your health, for weight loss, or to prevent heart disease. Inevitably, a year or so later, another study finds that the initial health claims were either exaggerated or just not true.

The headlines read, “Vitamin E prevents cancer!” Wait a minute; no it doesn’t after all. News flash: “Antioxidants prevent heart disease!” Oops, sorry, actually they don’t. We read first that calcium is great for osteoporosis, but later find that it can damage the heart.

The ultimate case of nutritional advice being reversed relates to dietary fats. In the late 1950s, heart disease was on the rise, and the American Heart Association blamed saturated fats found in meat and dairy. Hydrogenated fats were touted as a healthier alternative, less likely to cause heart disease, and the news was all over the media. Doctors convinced their patients to switch to “healthier” hydrogenated fats in margarine and shortening, and away from the “bad” fats in butter and meats.

But after several years of eating these fats, and further studies on their effects, it became obvious that hydrogenated fats (and the trans fats that accompany them) were not the panacea they were claimed to be. In fact, they were found to be a major cause of heart disease. A 2006 study in the journal Nutrition in Clinical Practice estimated that trans fats cause between 30,000 and 100,000 deaths per year from heart disease in the U.S. Trans fats are now prohibited for restaurant use in several U.S. cities, throughout Canada, and most of Europe.

What is going on here? How could a food touted as a savior from heart disease end up being one of the worst causes of it? How could medical science be so wrong?

Part of the problem lies in a lack of understanding of the underlying principles of nutrition. In chiropractic school 30 years ago, we were taught all the usual nutritional concepts. We learned about proteins, essential fats, vitamins, minerals, etc. But the first few classes were devoted to the basic principles of nutrition. Based just on these principles, we were warned against trans fats long before the research exposed their dangers.

The first principle of nutrition is simple: The more you process a food, the more you reduce its nutritive value. If it is highly processed, it will likely become harmful. Think of sugar, which is vital to our bodies, but toxic if eaten in a highly purified form. Hydrogenated fats are made under unnatural conditions including exposure to chemicals, high heat and pressure. This certainly is enough to change an otherwise healthy food into a toxic one. So we were advised to avoid them, based on this principle, long before the research showed them to be unhealthy. That turned out to be good advice.

This is the difference between the “reductionist” approach to nutrition, used by modern medical science, and the holistic approach favored by wellness practitioners. The reductionist approach is based on the idea that the health value of foods can be traced to isolated nutrients. Identify these nutrients, purify and concentrate them, and you will have a powerhouse of a supplement that can be taken as a pill, or added back into our foods to keep us healthy.

The holistic approach to nutrition it is based on the idea that while foods do have different health-promoting properties (citrus fruits prevent scurvy; liver is rich in iron, to build up blood; and fish tend to be rich in healthy fats), if you try to isolate these nutrients too much, the value is lost. There is more value in an intact, whole food than in any highly refined, concentrated vitamin pill.

The second principle was that the quality of a food is affected by the conditions in which it was raised. For example, “factory-farmed” beef cattle are not allowed to eat their natural food (grass) but are fed grains instead to fatten them up. This makes them overweight, stressed and prone to infections, so many are kept on a steady diet of antibiotics. It only makes sense that the meat from these animals will not be as healthy as the meat from a grass-fed, active, free-range animal. Also, based on this same principle, veggies grown in healthy, organic soil will be more nutritious for you than veggies grown on depleted soil with artificial fertilizers.

From a wellness viewpoint, nutrition is really pretty simple. Eat minimally processed, whole foods; avoid sweets; prepared foods; and (to borrow from author Michael Pollan) those with five or more ingredients. Include raw foods regularly. Avoid sweeteners of any kind, natural or otherwise. Choose organic and free range over factory farmed.

Don’t worry too much if some medical researcher finds organic broccoli causes brain tumors — just wait a few years and the next study will likely set the record straight. (More on this topic in my next column.)

Dr. Michael Noonan practices chiropractic, acupuncture and other wellness therapies in Old Town.